package com.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.reggie.common.BaseContext;
import com.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/*
* 检查用户是否已经完成登录
* */
@Slf4j
@WebFilter(filterName ="loginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器
    public static final AntPathMatcher PATH_MATCHER=new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletResponse response= (HttpServletResponse) servletResponse;
        HttpServletRequest request= (HttpServletRequest) servletRequest;
        //1.获取本次请求的url
        String requestURI = request.getRequestURI();
        //2.本次请求是否需要处理
        String[] urls=new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };//不需要处理的请求路径
        boolean check = check(urls, requestURI);
        if (check) {
            //放行
            filterChain.doFilter(request,response);
            return;
        }
        //4-1.需要处理的请求，判断登录状态，如果已经登录，则直接放行
        Object employee1 = request.getSession().getAttribute("employee");
        if (employee1!=null){
            log.info("用户已登录，用户id为{}",employee1);

            //把id设置进threadlocal
            Long empId= (Long) employee1;
            BaseContext.setCurrentId(empId);

            //放行
            filterChain.doFilter(request,response);
            return;
        }
        //4-2，判断登录状态，如果已经登录，则直接放行
        Object employee2 = request.getSession().getAttribute("user");
        if (employee2!=null){
            log.info("用户已登录，用户id为{}",employee2);

            //把id设置进threadlocal
            Long empId= (Long) employee2;
            BaseContext.setCurrentId(empId);

            //放行
            filterChain.doFilter(request,response);
            return;
        }
        log.info("没有用户登录");
        //5.如果没有登录则返回未登录结果
        /*
        * request.js中有一个响应拦截器，有下面这句：
        * if (res.data.code === 0 && res.data.msg === 'NOTLOGIN') {// 返回登录页面
        * */
        //通过输出流的方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /*
    * 路径匹配，检查本次请求是否需要放行
    * */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
